Blends of an ethylene/alkyl acrylate copolymer with an ethylene/propylene copolymer having a melting point greater than 100° C., or polypropylene with an ethylene/ethyl acrylate copolymer in the presence of a peroxide have been disclosed. See, e.g., Japanese Patent Application JP6329744A and U.S. Pat. No. 4,234,656.
Thermoplastic elastomer compositions made by dynamic crosslinking have also been disclosed. See, e.g., U.S. Pat. No. 4,710,544 and EP0964890 B1.
It is desirous to develop a new composition that maintains the preparation simplicity of an unmodified blend, but has an improved high temperature performance approaching that achievable in compositions where the compositions have been reactively modified by a crosslinking process.